flowchart LR;
a[Blank period<br><tt>nullPeriod</tt>] --> b1;
subgraph Stimulus[Stimulus, <tt>* numBlocks</tt> ]
b1[Inner annulus<br><tt>onLength</tt>] --> br1[Blank<br><tt>offLength</tt>];
br1 --> b2[Outer annulus<br><tt>onLength</tt>];
b2 --> br2[Blank<br><tt>offLength</tt>];
end;
br2 --> c1[Good bye];
style Stimulus fill:#ddd,stroke:#333,stroke-width:2px
Basic Vision stimuli for 7T
Stimuli for fMRI experiments written in PsychoPy
Stimuli can either be run via command line (my preferred) if PsychoPy module is installed or via the PsychoPy GUI (to be tested more completely).
Stimulus programs
retinotopy.py - Sliding checkerboard annuli / wedges
Expanding, contracing rings of checkerboard segments that move against each other (step size and direction change probability can be changed)
usage: ./retinotopy.py [-h] [--vpixx] [--no-vpixx] [--coding-window]
[--screen-size SCREEN_SIZE SCREEN_SIZE] [--check-timing]
[--use-gui] [-obs OBSERVER] [-dir {exp,con,cw,ccw}]
[-ct CYCLETIME] [-nc NCYCLES] [-np NULLPERIOD] [-ss STIMSIZE]
[-dcw DUTYCYCLEWEDGE] [-dcr DUTYCYCLERING] [-ar ANGULARRATE]
[-cp CHANGEPROBABILITY] [-fp FLASHPERIOD] [-e] [-tr TR]
Travelling wedge or annulus stimulus for retinotopic mapping Exp, con, cw, ccw - as per
e.g. matlab implementations of the same.
optional arguments:
-h, --help show this help message and exit
--vpixx use VPIXX device
--no-vpixx run without VPIXX device (eg for testing)
--coding-window use small debug window for coding
--screen-size SCREEN_SIZE SCREEN_SIZE
screen size as width height
--check-timing check screen timing (false on MacOS: buggy timing!)
--use-gui use GUI to set parameters (overrides command line args)
-obs OBSERVER, --observer OBSERVER
Observer code
-dir {exp,con,cw,ccw}, --direction {exp,con,cw,ccw}
exp(anding) or con(tracting) rings, cw or ccw wedge
-ct CYCLETIME, --cycleTime CYCLETIME
How long to complete one cycle (seconds)
-nc NCYCLES, --nCycles NCYCLES
How many blocks?
-np NULLPERIOD, --nullPeriod NULLPERIOD
Duration of gray screen at start (seconds)
-ss STIMSIZE, --stimSize STIMSIZE
Stimulus size (fraction of screen height)
-dcw DUTYCYCLEWEDGE, --dutyCycleWedge DUTYCYCLEWEDGE
Duty cycle for wedge (fraction)
-dcr DUTYCYCLERING, --dutyCycleRing DUTYCYCLERING
Duty cycle for ring (fraction)
-ar ANGULARRATE, --angularRate ANGULARRATE
Angular rate of change
-cp CHANGEPROBABILITY, --changeProbability CHANGEPROBABILITY
Probability of direction change (per frame)
-fp FLASHPERIOD, --flashPeriod FLASHPERIOD
Flash period (seconds)
-e, --exportStimImage
Export stimulus (requires -tr)
-tr TR, --TR TR TR / dynamic scan time (required for -e)
./retinotopy.py --onLength 12 --offLength 0 --numBlocks 1 --nullPeriod 0eccLoc.py - Eccentricity localiser
Alternates two annuli (inner and outer) with a blank period for e.g.
usage: ./eccLoc.py [-h] [--vpixx] [--no-vpixx] [--coding-window]
[--screen-size SCREEN_SIZE SCREEN_SIZE] [--check-timing] [--use-gui]
[-on ONLENGTH] [-off OFFLENGTH] [-nb NUMBLOCKS] [-np NULLPERIOD]
[-ss STIMSIZE] [-fp FLASHPERIOD] [-g] [-v]
Visual stimulus that alternates a ring of given eccentricity A with an off block, the
eccentricity B with off block. The eccentricity (full height) corresponds to 1.0
(default), and A and B annuli together cover the full extent of that range
optional arguments:
-h, --help show this help message and exit
--vpixx use VPIXX device
--no-vpixx run without VPIXX device (eg for testing)
--coding-window use small debug window for coding
--screen-size SCREEN_SIZE SCREEN_SIZE
screen size as width height
--check-timing check screen timing (false on MacOS: buggy timing!)
--use-gui use GUI to set parameters (overrides command line args)
-on ONLENGTH, --onLength ONLENGTH
How long is the block on? (seconds)
-off OFFLENGTH, --offLength OFFLENGTH
How long is the block off? (seconds)
-nb NUMBLOCKS, --numBlocks NUMBLOCKS
How many blocks?
-np NULLPERIOD, --nullPeriod NULLPERIOD
Duration of gray screen at start (seconds)
-ss STIMSIZE, --stimSize STIMSIZE
Stimulus size (fraction of screen height)
-fp FLASHPERIOD, --flashPeriod FLASHPERIOD
Flash period (seconds)
-g Use the GUI to set params
-v Set verbose output
./eccLoc.py --onLength 12 --offLength 0 --numBlocks 1 --nullPeriod 0hemiLoc.py - Left vs Right hemifield localiser
Alternates two annuli (left and right) with a blank period for e.g.
./hemiLoc.py --onLength 12 --offLength 0 --numBlocks 1 --nullPeriod 0usage: ../hemiLoc.py [-h] [-bl BLOCKLENGTH] [-nb NUMBLOCKS]
[-np NULLPERIOD] [-ss STIMSIZE]
[-fp FLASHPERIOD] [-g] [-v]
Visual stimulus that alternates a hemifield stimulus between left
and right
optional arguments:
-h, --help show this help message and exit
-bl BLOCKLENGTH, --blockLength BLOCKLENGTH
How long is the block on? (seconds)
-nb NUMBLOCKS, --numBlocks NUMBLOCKS
How many blocks?
-np NULLPERIOD, --nullPeriod NULLPERIOD
Duration of gray screen at start (seconds)
-ss STIMSIZE, --stimSize STIMSIZE
Stimulus size (fraction of screen height)
-fp FLASHPERIOD, --flashPeriod FLASHPERIOD
Flash period (seconds)
-g Use the GUI to set params
-v Set verbose output
./hemiLoc.py -bl 12 -nb 10 -np 0 -ss 1.0 -fp 0.25Use at UoN
These block design and event-related stimuli are designed for use in the 7T scanner at the University of Nottingham. The current iteration emphasises - basic visual stimuli for localising retinotopic areas, LGN, etc. - simple visual task to maintain attention - fexibility to adjust block and event lengths to fit with TR / dynamic scan times of the fMRI experiments
Extensions
- WIP for documentation…
mermaiddiagrams, etc. (this document is rendered throughquartoso version information will relate to local compile.)
mermaid / version:
info
Acknowledgements
This repo is a fork of Alex Beckett’s https://github.com/AdvancedMRI/python_stimuli code with some modifications to run on later version of PsychoPy and different handling of command line args. 🙏